If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.

Re: [win32] - transparent and opacy

MessageBox takes 4 parameters, The second and third parameters are typed as LPCTSTR. If you are compiling as UNICODE, then these become LPCWSTR which is const WCHAR* which is const wchar_t*. If you are compiling as ASCII, LPCTSTR becomes LPCSTR which is const char*. As text is defined as const char *, this is ASCII. If you are compiling as UNICODE, then MessageBox would be expecting a type of const wchar_t* and not const char* which is being provided - which could be the reason for the error 87. Try changing MessageBox to MessageBoxA().

Victor is quite right. The value returned by GetLastError() is only valid when an error has actually occured and the function in error states that the error number can be obtained by calling this function. Calling GetLastError() in a context in which it is not expected to be called can provide erronous information. SetLayeredWindowAttributes() returns 0 on failure and only in that case should GetLastError() be used.

All advice is offered in good faith only. You are ultimately responsible for effects of your programs and the integrity of the machines they run on.

Re: [win32] - transparent and opacy

Originally Posted by 2kaud

MessageBox takes 4 parameters, The second and third parameters are typed as LPCTSTR. If you are compiling as UNICODE, then these become LPCWSTR which is const WCHAR* which is const wchar_t*. If you are compiling as ASCII, LPCTSTR becomes LPCSTR which is const char*. As text is defined as const char *, this is ASCII. If you are compiling as UNICODE, then MessageBox would be expecting a type of const wchar_t* and not const char* which is being provided - which could be the reason for the error 87. Try changing MessageBox to MessageBoxA().

Victor is quite right. The value returned by GetLastError() is only valid when an error has actually occured and the function in error states that the error number can be obtained by calling this function. Calling GetLastError() in a context in which it is not expected to be called can provide erronous information. SetLayeredWindowAttributes() returns 0 on failure and only in that case should GetLastError() be used.

i change for MessageBoxA() and i get the same error message.
1 question: SetLayeredWindowAttributes() is only for main window and not child window?
now i tested the same code with main window and works fine.. so what is needed for work with child windows?

Re: [win32] - transparent and opacy

But if read the MSDN documentation for SetLayeredWindowAttributes(), as pointed out by Victor, this function only works on child windows with Windows 8/8.1. What OS are you using? If you are using a Windows OS prior to version 8 then this function only works for top level windows. Read the MSDN on-line documentation!

All advice is offered in good faith only. You are ultimately responsible for effects of your programs and the integrity of the machines they run on.

Re: [win32] - transparent and opacy

Originally Posted by 2kaud

But if read the MSDN documentation for SetLayeredWindowAttributes(), as pointed out by Victor, this function only works on child windows with Windows 8/8.1. What OS are you using? If you are using a Windows OS prior to version 8 then this function only works for top level windows. Read the MSDN on-line documentation!

i'm trying learn how use Regions, but i have 2 questions:
1 - i belive that i can do it pixel by pixel. but i'm confused... but i think that i can do it... at least i did with VB2010;
2 - with Regions, can i do opacy?

Re: [win32] - transparent and opacy

"With WS_EX_COMPOSITED set, all descendants of a window get bottom-to-top painting order using double-buffering. Bottom-to-top painting order allows a descendent window to have translucency (alpha) and transparency (color-key) effects, but only if the descendent window also has the WS_EX_TRANSPARENT bit set. Double-buffering allows the window and its descendents to be painted without flicker."

but i'm confused
i think that, when i create the main window, i must add the WS_EX_TRANSPARENT extended style and add the WS_EX_COMPOSITED with child window extended style.
but or i don't understand what these means or i did something wrong
because the STATIC control isn't created

Re: [win32] - transparent and opacy

With my test code (as posted previously), setting the main window as WS_EX_COMPOSITED and setting the static control WS_EX_TRANSPARENT has no effect as expected (non Windows 8 computer). I still get the static control created as if these styles weren't specified.

All advice is offered in good faith only. You are ultimately responsible for effects of your programs and the integrity of the machines they run on.

* The Perfect Platform for Game Developers: Android
Developing rich, high performance Android games from the ground up is a daunting task. Intel has provided Android developers with a number of tools that can be leveraged by Android game developers.

* The Best Reasons to Target Windows 8
Learn some of the best reasons why you should seriously consider bringing your Android mobile development expertise to bear on the Windows 8 platform.